No abstract

No abstract

Induction chemotherapy or concurrent chemotherapy with radiotherapy can preserve laryngeal function without a detrimental effect on survival in patients with advanced laryngeal cancer. However, systemic chemotherapy with traditional injection often causes side effects. In this study, methoxy poly(ethylene glycol)-poly(lactide-co-glycolide) (MPEG-PLGA) nanoparticles (NPs) were developed as a carrier for paclitaxel, a potent cytotoxic agent. The NPs were prepared by an emulsification-solvent evaporation method with the particle size and zeta potential around 153.3+/-41.7 nm and -5.36 mV. Transmission electron microscopy showed that the NPs were homogeneous and spherical in shape. Differential scanning calorimetry and X-ray powder diffractometry did not detect any crystalline drug in the NP samples. High-performance liquid chromatography was used to measure the drug loading, encapsulation efficiency, and in-vitro drug release. The drug loading efficiency was (5.35+/-0.75)% and encapsulation efficiency was (75.56+/-2.61)%. In the in-vitro drug release study, paclitaxel was released from the NPs in a slow but time-dependent manner. In-vitro cytotoxicity of the paclitaxel-loaded NPs was investigated by using human laryngeal cancer Hep-2 cells. The anticancer activity of paclitaxel-loaded NPs was comparable with the free paclitaxel. No significant cytotoxicity was observed in blank MPEG-PLGA NPs. Laser scanning confocal microscopy was used to observe the uptake of fluorescent coumarin-6-loaded NPs by Hep-2 cells. We conclude that the formulation of NPs inhibits Hep-2 cell growth to a similar extent as free paclitaxel injection. These results suggest that MPEG-PLGA NPs may have potential as an alternative delivery system for paclitaxel.

No abstract

A folate-functionalized carbon dot-based nanocarrier system has been successfully synthesized for cancer cell targeted drug delivery.

asymmetric feature, which is in direct contrast with the traditional Lorentz resonance. [2] In 1961, Ugo Fano discovered this resonance mode when he studied the auto-ionization state of atoms. [3] With the development of micro-nano science, sharp Fano resonances have been observed from the asymmetric split-ring resonators based on metasurface in recent years. [4,5] The asymmetry of the spectrum is mainly due to the symmetry breaking of the split ring structure, further causing the coupling of the fundamental mode (bright mode) and the high order mode (dark mode). The sharp Fano resonance can be widely used in notch filter, narrowband filter, photo-switching device, slow light device, etc. [6-9] In addition, Fano resonance of the metasurface is significantly sensitive to the characteristics of the external dielectric environment, thus effectively improving the sensitivity of the sensor, e.g., biochemical sensor. [10,11] Furthermore, Fano resonance based on metal metasurface provides a new approach for terahertz (THz) application, which can adjust the enhanced THz local electrical field by controlling the micro-nano material parameters and structural parameters. [12-14] Many types of researches relating to THz Fano resonance have been explored and implemented one after another, especially in terms of the control of THz Fano resonance intensity. [15] Those common control methods involve with the thermal, electrical, optical, hybrid opto-thermal, and hybrid opto-electrical routes. [16-20] In essence, these methods change the number of carriers in the resonance position in order to achieve the purpose of controlling the intensity. Optical control of Fano resonance intensity has attracted widespread attention. The common approach is to cover the thin photoactive materials on the surface of THz Fano meta devices, and the selected photoactive materials are germanium (Ge), molybdenum disulfide (MoS 2), perovskite, lead iodide (PbI 2), graphene, and so on. [18,21-25] And the modulation depth could be up to 90%. However, some disadvantages are still obvious. On the one hand, due to the inherent shortcomings of the thin photoactive materials (generally polycrystalline films), such as high lattice defect concentrations, it had to rely on high pump power in order to obtain 90% modulation depth, thus inducing enough carrier amounts. Therefore, expensive femtosecond pulse was generally needed as the optical pump source. [18,21-24] On the It is one of the effective methods to modulate Fano resonance intensity by adding the thin photoactive material in the Fano metadevice and then light pumping them. However, most photoactive materials not only depend on high power femtosecond pulse, but also violently destroy the initial Fano resonance, thus deteriorating the modulated amplitude range (less than 0.35 in previous reports). This study introduces a terahertz (THz) Fano resonator based on Si photoactive substrate (SPS) which is modulated by low power 1064 nm continuous wave without additional photoactive materials. 90% modulation dep...

As is well known that the specific capacitance of supercapacitors cannot be improved by increasing the mass of the deposited MnO 2 films, which means an appropriate deposition duration is important. In this study, nanobelt-structured MnO 2 films were prepared by the electrochemical deposition method under different deposition time to explore the effects of electrodeposition time change on the microstructure and electrochemical properties of this material. Benefiting from the microstructure of the MnO 2 films, the transfer properties of the charged electrons and ions were promoted. Meanwhile, a 3D porous nickel foam was chosen as the deposition substrate, which rendered an enhancement of the MnO 2 conductivity and the mass of the active material. The enhanced specific capacitance and specific surface area attributed to synergistic reactions. Subsequently, the electrochemical performances of the asprepared materials were analyzed via cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) tests. Results show that the optimum sample deposited for 50 s has a specific capacitance of 291.9 F g À1 at the current density of 1 A g À1 and lowest R ct . However, its electrochemical stability cannot come up to the level of the 300 s sample due to the microstructure change.

No abstract